Refrigerating system



' y 1936- 7 c. G. MUNTERS 2,042,355

REFRIGERAT ING SYSTEM Filed July 25, 1952 IN VEN TOR.

Car/ 660(9 Munzers ATTORNEY Patented M ize, 1936 h [2,042,355

REFRIGERA'IIN G SYSTEM Carl Georg Munters, Stockholm, Sweden, as-

signor, by mesne assignments, to Servel, Inc., Dover, Del., a corporation of Delaware Application July 23, 1932, Serial No. 624,223 In Germany August 1, 1931 12 Claims. (Cl. 62-178) This invention relates to refrigeration and cates with the lower part of an absorber 2| more particularly to a system for producing rethrough conduit 22. The absorber may be cooled frigeration by the evaporation of a plurality of in any well known manner and is shown provided refrigerants. with heat radiating fins 23 for air cooling. The

Absorption refrigerating systems have been interior of the absorber 2| is, provided with a 5 proposed utilizing several,refrigerants of which plurality of bafile plates 24 as well known in the one is absorbed and then expelled from soluart. The bottom of the-absorber 2| is contion by heat and another is condensed without nected throug u t D p q dh being dissolved in an absorption liquid. Such exchanger 21, and conduit 28 to the upper part systems require the use of refrigerants which mm of the generator I 0. The we P t Of the 10 dense at approximately the same pressures and erator I0 ,is connected through conduit 29, liquid temperatures. heat exchanger 21, and conduit 30 to' the upper This invention contemplates a continuous abpart of the absorber 2|. A control valve 3| in sorption system of the two pressure type utilizconduit 30 may be oper d m nua r a l5 ing several refrigerants which condense at apmatically in a y manner known in the art, for proximately the same temperatures but at difce, responsive to generator P e ferent pressures, thereby greatly increasing the v t p atu ,choice of refrigerants and making possible low T e t p Of the absorber 2| is ee ed through refrigerating temperatures. A system in accordconduit 32 to one end of a condenser 33, the other ance with this invention is particularly appliend of which communicates with the lower part 20 cable for large installations or commercial ma- Of e evap ator l8 through u t 3 The chines where low refrigerating temperatures may condenser 33 hereinafter referred to as the bube required and operating personnel is available. tane condenser may be cooled in any well known A further object of this invention is to provide manner d is shown v d With heat radiatsuch a refrigerating system which continues to e fin 5 fo air co 25 produce refrigeration for an appreciable length For t P p Of this. description. Water i of time after the operating means have been d as t e b o p q ammonia as the shut down. soluble refrigerant, and isobutane as the insoluble Further objects and advantages will be aprefrigerant. When' the generator I0 is heated,

parent from the following description taken in ammonia vapor is expelled from solution in the. 30 connection with the accompanying drawing in water and passes upwardly through conduit l4 which the figure shows schematically, with parts and rectifier l5 to the ammonia condenser 16. in vertical section, a system contemplated by Some ammonia condenses in the c d portion 1 this ihvention. 36 of conduit l4 and the liquid accumulates in Referring to the drawing, a generator ill the rectifier I 5 which is thus maintained at such adapted to contain a solution of refrigerant in an a temperature that water vapor which may pass absorption liquid, such as ammonia in water, is upwardly through conduit M with the-ammonia heated by any suitable means, such as a gas vapor is condensed out and drains back to the burner H in the flue I2. The generator I0 as generator through conduit 40 represented is of the vertical type with a plu- Liquid ammonia from the condenser I B flows rality of baflies in its upper portion which forms through conduit 19 and the pressure reducing an analyzer, as hereinafter described. valve 20' into the lower part of the evaporator ID.

The top of the generator l0 communicates The latter is also supplied w l q isobutane through conduit l4 and rectifier IS with a mm from condenser 33 as hereinafter described. In

' denser Hi. This condenser is hereinafter rethe evaporator. both the ammonia and isobutane '45 ferred to as the ammonia condenser and is suitevaporate and the resulting gas mixture flows ably cooled by circulating cooling water or air. through conduit 22 into the absorber 2!.

In the latter case the condenser is provided with It is apparent that a pressure diflerence beheat radiating 'fins H, as illustrated. The amtween the generator on one hand and the ab- 0 monia condenser I6 communicates with the lower sorber and evaporator on the other is maintained part ,of the evaporator l8 through conduit I9 in by valve 20 in the ammonia line l9, valve 3| in which there is a pressure reducing valve 20. This I the weak liquor line 30, and pump 28 in the-strong valve may be operated manually or automatically liquor line '25. Due to this pressure difference in any of the several ways known in the art. when the. generator III is heated, weak absorp- The upper part of the evaporator l8 communition liquid flows from the generator through con- 55 duit 29, liquid heat exchanger 21, conduit 30, and control valvev 3| into the upper part of the absorber 2| where it flows downwardly over the baflle plates 24 absorbing ammonia out of the gas mixture.

Enriched absorption liquid flows from thebottom of the absorber through conduit 25 and is forced by pump 26 through the liquid heat exchanger 21 and conduit 23 to the upper part of the generator ill where it flows downwardly over baiile plates l3 in contact with and counterflow to the rising vapor expelled from solution in the generator whereby an analyzing efiect is obtained to remove some of the water vapor from the ammonia.

Isobutane passes from the top of the absorber 2| into the condenser 33 which is maintained at such a temperature that, under absorber pres sure, the isobutane liquefles and flows through conduit 34 into the evaporator l3.

It is preferable that conduit 34 be a tube of small diameter so that any ammonia which may enter the butane condenser 33 will be carried downwardly into the evaporator by the liquid isobutane. It will be understood that ammonia gas might also be ventedfrom the discharge end of the butane condenser 33, as is well known in the art, into the ammonia line is on the side of the control valve 20 toward the, evaporator l3.

At starting, the solution of ammonia and water may stand in the generator l0 and absorber 2|, and isobutane in the evaporator lB,-to the levels A. When the generator is heated, the liquid level therein falls say to the level 13 and due to the addition of ammonia in the evaporator it, the liquid therein rises to some higher level B, but the liquid in the absorber 2| remains substantially at the level A. The liquid head in the absorber 2| above the connection of conduit 22 is balanced by corresponding liquid columns standing in the ammonia conduit I9 and isobutane conduit 34 to the evaporator i 8.

When the gas burner ii and pump 26 are shut down, the valve 20 in the ammonia line should be closed. Obviously a separate automatic shut-oil valve could be provided in this line to the same end. The pressure in the generator continues to force liquid through conduit 29, heat exchanger 21, and conduit 30 into the absorber until the liquid therein rises to some level C. Thus the amount of liquid in the absorber is considerably increased during the shut down period. The two refrigerants in the evaporator I8 continue to evaporate and the ammonia is absorbed out of the gas mixture bubbling through theliquid in the absorberfi- The isobutane continues to circulate through the absorber, condenser 33, and evaporatorlB as long as evaporation takes place in the latter.

It will be obvious tothose skilled in the art that various other changes may be made in the construction and arrangement without departing from the spirit of the invention and therefore the invention is not limited to what is shown in the drawing and described in the specification but only as indicated in the following claims.

I claim:

1. The method of refrigeratin which includes evaporating a plurality of liquid cooling fluids in the presence of each other, and separately con-g in'g in the presence of each other during the fluids at a different pressure. and again evapo- 5 rating the liquids in thepr'esence of each other. 3. The method of refrigerating which'includes passing a plurality of fluids through their respective evaporating-condensing cycles, said fluids beevaporating portions of the cycles and under different pressures during the condensing portions tion, expelling the ammonia as vapor from solution. condensing the expelled ammonia under certain temperature and pressure conditions, condensing the vapor'ous isobutane at a different 80 pressure, and again evaporating the condensed fluids in the presence of each other. 7

6. A refrigerating system including a generato a condenser, an evaporator, and an absorber forming a circuit for a cooling fluid, a pressure 35 reducing control valve in said circuit between said condenser and evaporator, means for controlling the circulation of absorption liquid between said generator and absorber and maintaining a pressure diil'erence therebetween, and an auxiliary 40 I circuit for a second cooling fluid comprising said evaporator, said absorber, and a second condenser through which a second cooling fluid passes from the absorber to the evaporator.

'I. A refrigerating system including a generator, 45

an absorber, means for circulating absorption liquid from said generator through said absorber and maintaining a pressure difference therebetween, an evaporator connected to discharge gas into said absorber, a first condenser connected 50 to receive vapor from said generator anddischarge liquid into said evaporator, pressure reducing means between said condenser and evaporator, and a second condenser connected to receive vapor from said absorber and discharge 65 liquid into said evaporator.

8. A refrigerating system including a generator, an absorber, a conduit for weak absorption liquid from said generator to said absorber,a control valve in said conduit, means for trans- 60 fer-ring enriched absorption liquid from a region of low pressure to a region of high pressure in a path of flow from the absorber to the generator, an evaporator, a conduit for gas from said evaporator to the absorber, a first condenser connected 65 v between said generator and evaporator, a pressure reducing valve in the connection between said condenser and evaporator, and a second condenser connected between and in unrestricted fluid communication with both said absorber and evaporator. r

'9. A refrigerating system including a first circuit for cooling fluid having a high pressure portion including a generator and a condenser, and a low pressure portion including an evaporator and an absorber, and a second condenser connected between said absorber and evaporator to form therewith a circuit for a second cooling fluid.

10. A refrigerating system including a generatqr, a condenser, and an evaporator, an absorber connected to form a path of flow for a cooling fluid, pressure reducing means in said path of flow between said condenser and evaporator, a second condenser orbitly connected in unrestricted fluid communication with said absorber and evaporator to form a circuit for ,a; second cooling fluid, a conduit for weak absorption liquid from said generator to said absorber, a control valve in said conduit, and a pump connected to return enriched absorption liquid from the absorber to the generator.

11. A refrigerating system including a generator, an absorber, a conduit for weak absorption liquid from said generator to said absorber, a control valve in said conduit, means for transferring enriched absorption liquid from a region of low pressure to a region of high pressure in a path of flow from the absorber to the generator,

' an evaporator, a conduit for gas from said evaporator to the absorber. a first condenser connected between said generator and evaporator, pressure reducing and shut-oil means in the connection between said condenser and evaporator, and a second condenser connected between and in i'ully open fluid communication with both.

said absorber and evaporator.

12. A refrigerating system including a generator, heating means for said generator, an absorber, a conduit for weak absorption liquid from said generator to said absorber, a control valve in said conduit, a pump for returning enriched absorption liquid from the absorber to the generator, an evaporator, a conduit for gas from said evaporator to the absorber, a first condenser connected between said generator and evaporator, pressure reducing and shut-on means in the connection between said condenser and evaporator adapted to be closed when said pump and generator heating means are shut down, and a second condenser connected between and in fully open fluid communication with both said absorber and evaporator.

cant. GEORG MUN'I'ERS. 

